Input keywords (epm.inp)
EPM code input format (epm.inp)
# BEWARE: you cannot comment out tags with # in EPM!
# any occurrence of a tag will be found and read.
# These parameters are only for epm2bgw
real_or_complex 1 # 1 = real, 2 = complex. default is complex.
wfng_flag T # Write wavefunction file (default F)
wfng_file WFN # filename (default WFN)
KPointNumbers 5 5 5 # number of points in k-grid in each direction b1,b2,b3
KPointOffsets 0.5 0.5 0.5 # shift in k-grid in each direction b1,b2,b3
rhog_flag T # Write density file (default F)
rhog_file RHO # filename (default RHO)
vxcg_flag T # Write xc potential file (default F)
vxcg_file VXC # filename (default VXC)
vxc_flag T # Write VXC matrix element file (default F)
vxc_file vxc.dat # filename (default vxc.dat)
vxc_diag_nmin 1 # minimum band to write diagonal matrix elements (default 0)
vxc_diag_nmax 8 # maximum band to write diagonal matrix elements (default 0)
vxc_offdiag_nmin 1 # minimum band to write off-diagonal matrix elements (default 0)
vxc_offdiag_nmax 8 # maximum band to write off-diagonal matrix elements (default 0)
disable_symmetries F # set to true to write no symmetries (default F)
# EPM does not really do a spin-polarized calculation, but can write two copies of everything
nspin 1 # set to 2 to write spin up and spin down (default 1)
temperature 0 # kT in eV for Fermi-Dirac distribution occupations (only for BerkeleyGW output)
# The Fermi level is taken as the mid-gap.
FFTGrid 16 16 16 # FFT grid for computing density (default: determined from EnergyCutoff)
# These parameters are common to epm and epm2bgw
# Set form factor parameters (see examples in form_factors.dat),
# or default is to use V(q) from atomPotentialMod (only for H,Si,Ga,As)
FormFactors 5.43 -0.224 0.055 0.072 0.000 0.000 0.000
# 0 is for LAPACK direct diagonalization (default), 1 for conjugate gradients
DiagonalizationSwitch 0
AbsoluteTolerance -1.0d0 # tolerance for LAPACK diagonalization (default -1 means machine precision)
CGIterationPeriod 5 # parameter for conjugate gradients (default 3)
CGTolerance 1.0d-10 # parameter for conjugate gradients (1d-5)
InputEnergiesInEV # Rydberg is default
EnergyCutoff 11.0 # plane-wave cutoff for the potential (and wavefunctions)
NumberOfDimensions 3 # dimensionality of the system (default 3)
#LatticeConstantFormat Angstrom # default is Bohr
LatticeConstant 10.2612 # in units given above
LatticeVectors # in lattice constant units
0.0 0.5 0.5
0.5 0.0 0.5
0.5 0.5 0.0
NumberOfAtoms 2
NumberOfSpecies 1
ChemicalSpeciesLabel # index, atomic number, name
1 14 Si
AtomicCoordinatesFormat ScaledByLatticeVectors
# ScaledByLatticeVectors (default) is in crystal coordinates
# ScaledCartesian is in units of LatticeConstant
AtomicCoordinatesAndAtomicSpecies # x, y, z, species index
-0.125 -0.125 -0.125 1
0.125 0.125 0.125 1
NumberOfBands 8
NumberOfOccupiedBands 4 # note: you cannot really do metals, occupations are fixed.
KPointsScale ReciprocalLatticeVectors # default; other choice is TwoPi/a
KPointsList 19 # number of k-points supplied
0.100000000 0.100000000 0.100000000 2.0 # kx, ky, kz, weight (will be renormalized)
0.100000000 0.100000000 0.300000000 6.0
0.100000000 0.100000000 0.500000000 6.0
0.100000000 0.100000000 0.700000000 6.0
0.100000000 0.100000000 0.900000000 6.0
0.100000000 0.300000000 0.300000000 6.0
0.100000000 0.300000000 0.500000000 12.0
0.100000000 0.300000000 0.700000000 12.0
0.100000000 0.300000000 0.900000000 12.0
0.100000000 0.500000000 0.500000000 6.0
0.100000000 0.500000000 0.700000000 12.0
0.100000000 0.500000000 0.900000000 6.0
0.100000000 0.700000000 0.700000000 6.0
0.300000000 0.300000000 0.300000000 2.0
0.300000000 0.300000000 0.500000000 6.0
0.300000000 0.300000000 0.700000000 6.0
0.300000000 0.500000000 0.500000000 6.0
0.300000000 0.500000000 0.700000000 6.0
0.500000000 0.500000000 0.500000000 1.0
# for plotting band structures; used if KPointsList not present
NumberOfLines 4
NumberOfDivisions 20
KPointsScale ReciprocalLatticeVectors # same as above
KPointsAndLabels
0.500 0.500 0.500 L
0.000 0.000 0.000 G
0.500 0.000 0.500 X
0.625 0.250 0.625 U
0.000 0.000 0.000 G
# These parameters are only for epm. Find band gap and effective mass.
gap_flag F # default F
gap_file bandgap.dat # filename (default gap.dat)
# Note: effective mass only works for silicon-like band structures.
mass_flag F # default F
mass_file effmass.dat # filename (default mass_file)